Apparatus for treatment of fabrics with liquid ammonia

ABSTRACT

The invention relates to an apparatus for the treatment of fabrics with liquid ammonia to improve several properties of the fabrics. The apparatus is provided with control means controlling the tensions to which the fabrics are subjected during the treatment.

United States Patent Skaathun et al. 1 May 23, 1972 APPARATUS FOR TREATMENT OF 1 rences Cited FABRICS WITH LIQUID AMMONIA UNITED STATES PATENTS [72] Inventors: Olav Skaathun, Kolbotn, Norway; Walter 2,641,121 6/1953 Belcher ..68/5 D X S. Troope, Latham, N.Y. 2,727,378 12/1955 Cook ..68/5 D 3,528,763 9/1970 Runton ..8/149.1 X [73] Assgnee Temle Devehpmem 3,367,039 2/1968 Jacobsen ..68/5 D x orway 22 Filed; 5 1970 FOREIGN PATENTS OR APPLICATIONS 211 App], ,9 7 453,541 9/1936 Great Britain ..26/] 8.5

Related US. Application Data Primary Examiner-William 1. Price [63] Continuation-impart of Ser. No. 834,730, June 19, mack 9 an (med 57 ABSTRACT [52] "68/51), 68/19-1 The invention relates to an apparatus for the treatment of [51] Int. Cl ..D06c l/00 fabrics i liquid ammonia to improve several properties of [58] Field of Search ..8/149.1, 149.2, 149.3; 68/5 D, the fabrics The apparatus is provided with control means Com trolling the tensions to which the fabrics are subjected during the treatment.

19 Claims, 6 Drawing Figures PATENTEU MAY 23 1972 SHEET 1 OF 3 m: NS m2 o NAM APPARATUS FOR TREATMENT OF FABRICS WITH LIQUID AMMONIA This application is a Continuation-in-Part of US. Pat. Application Ser. No. 834,730, filed June 19, 1969, now abandoned, and relates to apparatus for the treatment of fabrics and, more particularly, to apparatus for treatment of fabrics with liquid ammonia to improve the extensibility or stretch, resistance to shrinkage and resistance to wrinkling or creasing of such fabrics and to methods for operating'such apparatus.

U. S. Pat. No. 3,406,006 discloses and describes a method for the treatment of woven or knitted fabric containing natural or regenerated cellulosic fibers to improve the extensibility or stretch, resistance to shrinkage and resistance to wrinkling or creasing of such fabrics. In such method, the fabric is impregnated with liquid ammonia and, while so impregnated and, while in an atmosphere saturated with ammonia vapor, tension is applied to the fabric and the ammonia is removed. Such tension may be applied in the longitudinal or transverse direction of the fabric, or in both directions, depending on the improvement, and degree of improvement, desired. In addition to the tension applied, the improvement attained by the treatment in such patent depends, to some extent, on the time that the impregnated fabric remains saturated with liquid ammonia and the elapsed time before removal of the ammonia from the fabric. These times vary, from fabric to fabric, depending upon the composition of the fabric, its weight or thickness, whether the fabric is woven or knitted, the tightness of the fabric, and other factors.

The instant invention is concerned with apparatus and methods for carrying out the treatment of the aforementioned patent on a commercial and industrial scale and for the further treatment of fabrics treated in accordance with the method thereof. In order that this might be done, it is of course necessary that such apparatus be capable of processing large quantities of fabric with consistent and uniform results in a safe manner. Furthermore, it is important that such apparatus be capable of processing a wide variety of fabrics, fabrics that are light and fabrics that are heavy, fabrics with low cellulosic content and fabrics with high content, loosely woven or knitted and tightly woven or knitted fabrics, etc.

In the instant invention, such apparatus is provided, in a novel manner, by feeding the fabric from a fabric roll, or truck in which the fabric is loose, into and through axially aligned and sealed treatment chambers. From the treatment chambers, the treated fabric may be further treated and is re-rolled into a roll, or fed, loose, into a truck. The fabric is fed, continuously, through the treatment chambers and the speed of this fabric through the treatment chambers is controlled, by a feed drum in the treatment chambers. The tension on the fabric, fed into the treatment chamber, is controlled, in a novel manner by a feed drum intermediate the fabric supply and treatment chambers. The longitudinal tension on the fabric in the treatment zone is likewise controlled in a novel manner by a feed drum and compensators individually controlled, according to preset conditions.

The apparatus includes, among other things, three chambers. In the first chamber, the fabric is immersed and impregnated with liquid ammonia and, if desired, other materials, such as resins. The atmosphere in the first and second chambers is saturated with ammonia vapor so that, while in such chambers, the fabric remains ammonia saturated. In the second chamber transverse tension, when required, is applied to the fabric and the fabric is then fed around heated drums, or cans, to drive-off the liquid ammonia. In the third chamber, the treated fabric is steam washed to remove residual ammonia. Where other materials, such as resins, are used with the ammonia in the treatment chambers such other material may be cured or set as the treated fabric passes through the chambers.

The treatment chambers of the instant apparatus are maintained under slight negative pressure, that is, the pressure in the chambers is maintained at a level slightly below the pressure in the atmosphere surrounding the chamber. Such lower pressure, in the chambers, assures the desired atmospheric conditions within the chambers and prevents leakage of ammonia from inside of the chambers, into the atmosphere outside the chambers. Also, to prevent ammonia vapor from escaping from the chambers into the atmosphere outside of the chambers, the first and third chambers are provided with a seal or look through which, in entering the first chamber and being withdrawn from the third chamber, the fabric passes. These seals, or looks, are maintained under a slight vacuum, i.e., at a pressure lower than the chamber pressure and the ambient air surrounding the chambers. This is accomplished by interconnected ducts connected to a stack, from which air containing a relatively low percentage of ammonia vapor is withdrawn and exhausted into the atmosphere or otherwise disposed of. If desired, the ammonia vapor may be condensed, and concentrated for recycling. In most instances, however, the ammonia vapor content of such air is relatively small and, because of the cost of recovery, such vapors is exhausted to the atmosphere or is passed through an incinerator and burned.

During operation of the instant apparatus, the atmosphere in the first and second treatment chambers is maintained saturated with ammonia vapor at a pressure slightly below the ambient pressure of the air surrounding the chambers. In order to maintain the atmosphere in the first and second chambers saturated with ammonia vapor at the desired pressure and, at the same time, provide means for pressurizing the chambers with ammonia vapor during the start up and ammonia vapor exhaust during shut down, the first and second chambers are provided with a draft system and draft valves. The vapor removed through this draft system has a relatively high concentration of ammonia vapor. By passing the exhaust from this draft system through a recover unit, the ammonia vapor can be condensed and concentrated for recycling through the system.

The ammonia vapor air mixture in the first and second treatment chambers during normal operation is preferably in the range where the ammonia vapor constitutes an excess of percent by volume of the mixture. Such 90 percent by volume of ammonia vapor is well above the explosive or combustible mixture of ammonia vapor and air. When the apparatus of the instant invention is being started up, of course, the treatment chambers are filled with air and a large portion of such air must be purged, or removed from the chamber and replaced with ammonia vapor. Conversely, when the apparatus is being shut down, the ammonia and ammonia vapor must be removed from the treatment chambers. Because mixtures of air and ammonia vapor, in the range where the ammonia vapor constitutes from about 15 percent to 26 percent, by volume of the mixture, are explosive if sufficient heat for ignition is applied to the mixture, care must be exercised. In the method and apparatus of the instant invention, the treatment chambers are charged with ammonia vapor, from the top of the chambers and the air is purged from the bottom of the chambers during the starting up of the apparatus and, during shutting down of the apparatus, the ammonia vapor is removed from the top of the chambers and air is readmitted to the chambers from the bottom of the chambers. Thus, during the starting up and shutting down of the apparatus the air being purged from or admitted to the treatment chambers and the treatment mixture of air and ammonia vapor are kept separate. Hence, the volume of the mixture of air and ammonia vapor, while the ammonia vapor is being added to or removed from the treatment chamber and while the amount of ammonia vapor in the air and ammonia gas mixture is in the critical 15 percent to 26 percent explosive range, is maintained at the minimum.

The instant invention will be better understood from the following description and appended drawings of a preferred embodiment of the apparatus in which:

FIGS. 1A and 1B are a side elevational view, partly in section, of the apparatus of the instant invention, part of the apparatus being shown in FIG. 1A and the balance of the apparatus in FIG. 1B;

FIGS. 2A and 2B are a top plan view of the apparatus of FIGS. 1A and 1B, the apparatus in FIG. 2A being shown partly in section substantially along the top of the fabric, as the fabric passes through the apparatus; and

FIGS. 1C and 2C are views similar to FIGS. 1B, 2B, respectively, but show a modified form of the apparatus.

Referring to FIGS. 1A, 2A, the apparatus includes guide rolls 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 21, 23. Guide rolls 4, 6, are mounted for pivotal movement around shaft 22. Guide rolls 2, 8, 10, 12, 14, 16, 18, 20, 21, 23 are fixed for rotation about their respective axis. Roll 24, of feed rolls 24, 26, is driven by motor 28, the speed of motor 28 being controlled by rheostat 30 connected to tension roll 32. Tension roll 32 is mounted for pivotal movement about the axis of guide roll 20 on arms 34, 36. Arms 34, 36 are connected by arm 38 to piston rod 40 of air cylinder 42, for purposes hereinafter described.

Chambers A, B and C, separated, respectively, by partitions 50, 52, are enclosed by a wall 56, preferably insulated, which surrounds the chambers forming an airtight and vaportight enclosure. A seal, generally designated 60, having at one of its ends mating rolls 62, 64 and, at its opposite end, mating rolls 66, 68, and vented through duct 70, and damper valve 72, is fixed to one end of chamber A.

Guide rolls 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98 are mounted in fixed position for rotation about their respective axes in chamber A. If desired, and for reasons hereinafter explained, additional guide rolls 100, 102, 104, also fixedly mounted in chamber A, may also be provided. Feed roll 106, of feed rolls 106, 108, is driven, as will be later described, by constant speed motor 110. Liquid ammonia trough 112, having a drain 114, and a roller 116, mounted for vertical movement into and out of the trough in the direction of the arrows in FIG. 1A, is mounted in chamber A, intermediate guide rolls 74, 76. Tension roll 118, mounted on arms 120, 122 for pivotal movement about the pivot 124, is mounted intermediate, and below, guide rolls 80, 82, and is connected to rheostat 126. Pivotal movement of tension roll 118, about pivot 124, is regulated, as will be later explained, by air cylinder 128 having a piston and piston rod 130 connected to arm 120 by link 132. Liquid ammonia trough 134, having steam lines 136, 138 for heating the trough, is mounted in chamber A, near the top of the chamber. Liquid ammonia, as later described, is fed from a supply, not shown, to trough 134 through ammonia supply line 140. Pan 142 extends under feed rolls 106, 108, and drains liquid ammonia, squeezed from the fabric by feed rolls 106, 108, back into liquid ammonia trough 112. Duct 144, opening into chamber A at its lower end, 146 and upper end 148 and having draft valves 150, 152, 154, is connected to stack 156. Stack 156 may be vented to the atmosphere or, preferably, to an ammonia recovery system of any of the types commercially available.

Mating rolls 160, 162 are mounted in partition 50, partition and mating rolls 160, 162 separating chamber A from chamber B. Transverse fabric tensioning frame, generally designated 164, such as, a conventional tenter machine having, at the opposite marginal edges of the fabric tentering pins, not shown, upon which the edges of the fabric are impaled, for applying transverse tension to the fabric, where such transverse tension is required, is mounted in chamber B and is driven by motor 166 controlled by rheostat 126, as later explained. Liquid ammonia trough 168, having steam lines 170, 172, for heating the trough is mounted in chamber B, near the top of the chamber. Liquid ammonia is fed to trough 168 through ammonia supply line 174 from an ammonia supply, not shown, as later described. Heater drums 176, 178, 180, 182, 184, driven by motor 166 through gear box 186, are mounted in chamber B and are preferably heated by hot water or steam circulated through the drums.

Heater drum 176 may, for example, be heated with hot water and the remainder of the heater drums 178, 180, 182, 184 may be heated with steam, or the drums may be heated in various combinations with hot water and steam depending upon the requirements of the particular fabric being treated.

Guide rolls 190, 192, 194, 196, 198, 200 are mounted in chambers B, for rotation about their respective axes. Tension roll 202, pivotally mounted about the pivot 204 on arms 206, 208 and connected to rheostat 211, is mounted intermediate and below guide rolls 198, 200, the pivotal movement of tension roll 202 being controlled by air cylinder 210 having a piston and piston rod 212 connected to arms 204, 206 through arm 214. Tension roll 202, pivots 204, arms 206, 208, air cylinder 210, piston and piston rod 212 and arm 214 may be mounted intermediate and below guide rolls 198, 200, as shown in FIG. 1A, or may be mounted intermediate and below guide rolls 192, 194 as shown in phantom line 220, FIG. 1A. the position of tension roll 202, and associated mechanism, depending upon the type of fabric being treated and the number of the guide rolls 190, 192, 194, 196, 198, 200, being used.

Duct 222, open at its lower end 224 and having damper valve 226, extends downwardly from duct 228 into chamber B. Duct 228, having damper valves 230, 232 and open at its end 234 into chamber B, is connected to stack 156. Mating rolls 240, 242 are mounted in partition 52, separating chambers B and C.

Guide rolls 244, 246, 248, 250 and 252, 254, 256 are mounted in chamber C for rotation about their respective axes. Steam lines 260, 262, 264 mounted, respectively, about troughs 266, 268, 270 and steam lines 272, 274, 276, 278 mounted, respectively, above troughs 280, 282, 284, 286, are mounted in chamber C, each of the steam lines 260, 264, 266 and 272, 274, 276 and 278 having jets for discharging and directing streams of steam on to the fabric passing the lines, as will be later described.

Guide rolls 244, 246, 248, 252, 254, 256, are driven through gear box 290 driven by motor 292 through gear box 294, FIG. 23, as described later. Chamber C is heated by steam coils 296 extending across the top of chamber C inside housing 56. Duct 298, having a draft valve 300, opens at its lower end, 302, into chamber C and is connected, by duct 304, to stack 306. Duct is also connected to stack 306. A seal, generally designated 310, having at one of its ends mating rolls 312, 314, and, at its opposite end, mating rolls 316, 318, and vented through duct 320 and damper valve 322, is fixed to the end of chamber C.

Referring now to FIGS. 1B, 2B drive roll 324 of drive rolls 324, 326 is driven by motor 292, through gear boxes 294, 296. Guide rolls 328, 330, 332, 334, 336 and 338 are mounted, in fixed position, for rotation about their respective axes. Water spray 339 is mounted intermediate guide rolls 328, 330 for purposes later described. Transverse fabric tensioning frame, generally designated 340, such as, a conventional tenter machine as hereinbefore described, for applying transverse tension to the fabric, where such transverse tension is required, is driven by motor 292, through gear box 294. Fabric drier, generally designated 342, having heated drum 344 driven by motor 292, drum 346, belt 348 and guide rolls, is mounted at the end of tensioning frame 340. Driven roll 350, driven by motor 292, through gear box 352, is mounted above drier 342 with guide rolls 354, 356, fixedly mounted for rotation about their respective axes and mounted below drive roll 350. Drive roll 358, driven from gear box 352, is mounted at the end of arm 360 pivotally connected at 362 to frame 364. Guide roll 366 is fixedly mounted for rotation about its axes on fixed arm 370 for purposes later described.

In the operation of the apparatus of FIGS, 1A, 18, 2A, 2B, the fabric is fed from supply roll 400 at the left-hand end of FIGS. 1A, 2A through chambers A, B and C and the treated fabric is rerolled onto roll 402 at the right-hand end of FIGS. 1B, 28. Before starting the apparatus, liquid ammonia is placed in trough 112, and drive roll 116 is adjusted so that the fabric, in passing through trough 112, under drive roll 116, will be immersed and saturated with ammonia. In order to saturate the atmosphere in chambers A and B with ammonia vapor, draft valve 154 on duct 144 and draft valve 232 on duct 228 are closed and draft valves 150, 154, 226 and 230 are opened. Stack 156 is opened and, if provided with a blower,

the blower is turned on. Thus, air is withdrawn from the bottoms of chambers A and B. Liquid ammonia is fed through liquid ammonia supply pipes 140, 174, into troughs 134, 168 and steam lines 136, 138 and 170, 172 are turned on to heat troughs 134, 168 and vaporize the liquid ammonia in the troughs. As liquid ammonia, in the troughs, is heated, the ammonia is vaporized.

Because the ammonia vapor is lighter than air, the ammonia vapor rises to the top of chambers A and B and, from the top of chambers A and B, replaces the air being withdrawn from the bottom of the chambers through ducts 144, 222. Thus, there is formed'by the heated troughs 134, 168 a mixture of ammonia vapor and air in which the ratio of the ammonia vapor to the air rapidly increases until the critical range of 26 percent ammonia vapor, by volume, to air, is exceeded. As additional ammonia is vaporized, the lighter ammonia vapor pushes the air in chambers A and B downwardly and out of the chambers through ducts 144, 222 until the air in chambers A and B is displaced by the ammonia vapor. While the air is being so displaced from chambers A and B, no fabric is being fed through the chambers and the apparatus is not in operation. Thus, as the ammonia vapor is being built up in chambers A and B there is no mixing of the air below the ammonia vapor or mixture with the chamber air being displaced. Hence, the volume of the ammonia vapor air mixture, while such mixture is in the critical to 26 percent explosive range is kept to the minimum and, because the ammonia vapor from heated troughs 134, 168 is generated rapidly, it is only for a short interval of time that the ammonia vapor air mixture in chambers A and B is in the critical, explosive range. When chambers A and B are filled with ammonia vapor, the apparatus is ready for operation.

The fabric to be treated is fed from supply roll 400, around guide rolls 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 and between feed rolls 24, 26. The fabric then passes around guide roll 21, tension roll 32, guide roll 23, between mating rolls 62, 64 and 66, 68, around guide roll 74 and into trough 112 and the liquid ammonia in such trough.

In addition to the liquid ammonia in trough l 12 fabric treatment materials, such as resins, may be added to the liquid ammonia in such trough and deposited on the fabric as such fabric passes therethrough. From trough 112, the fabric, now saturated with liquid ammonia, passes over guide rolls 76, 78, between feed rolls 106, 108, around guide roll 80 and tension roll 118. The saturated fabric is then looped around guide rolls 84, 86, 94, 96, around guide roll 98, and through mating rolls 160, 162 and into chamber B. Where less treatment time is required, looping of the fabric around some of the guide rolls 84, 86, 94, 96 may be omitted. Where additional time is required, the fabric may also be looped around guide rolls 100, 102, 104.

In chamber B, if the fabric treatment requires transverse tension, tension is applied to the ammonia saturated fabric as the fabric passes through frame 164. Where such transverse tensioning is not required, frame 164 may be omitted or the fabric may be passed across frame 164 without transverse tension being applied to the fabric.

From frame 164, the fabric passes around heater drums, or heater cans, 176, 178, 180, 184, guide rolls 190, 192, tension roll 202, guide roll 200 and between mating rolls 240, 242 and then around guide rolls 244, 246, 284, 250, 254, 256 and, finally, guide roll 250. From guide roll 250, the fabric passes between mating rolls 312, 314 and 316, 318 and between guide rolls 324, 326. From drive rolls 324, 326, the fabric passes around guide rolls 328, 330, 332, 334, 336, 338, into drierframe 340. If required, for purposes later explained, as the fabric passes between guide rolls 328, 330, the fabric may be sprayed with water.

As the fabric passes through frame 340, transverse tension is applied to the fabric, if required, and the fabric is then passed around drier drum 334, driving roll 350 and the treated and dried fabric is then re-rolled onto roll 402 by roll 358.

Transverse tension, where such transverse tension is required, is applied to the fabric by frames 164 and 340. Longitudinal tension, i.e., tension in the direction of fabric feed, is applied to the fabric by the various drive rolls under the control of the various tensioning rolls and rheostats, or motor controls associated therewith. Preferably, the apparatus of the instant invention is driven with electric motors powered from a constant-voltage source, for example, from a motor generator.

Motor 110, driving feed rolls 106, 108, feeds the fabric at a constant speed, the speed of motor 1 10 being set to the treatment time requirements of the particular fabric undergoing treatment. Over and above the regulation of the speed of motor 110, treatment time can be increased or decreased by increasing or decreasing the looping of the fabric in rolls 84, 86, 94, 96, 100, 102 and 104 in chamber A, a decrease in the number of loops decreasing the treatment time and an increase in the number of loops increasing such treatment time.

Longitudinal tension on the fabric, as it enters chamber A and is fed by feed rolls 106, 108 is controlled by feed rolls 24, 26. By decreasing the speed of motor 28 and feed rolls 24, 26 relative to the feed speed of rolls 106, 108, longitudinal tension on the fabric is increased. By increasing the speed of feed rolls 24, 26 relative to feed rolls 106, 108, longitudinal tension is decreased. Air supply to air cylinder 42 is regulated so that, with tension roll 32 intermediate its uppermost and lowermost limits of arcuate movement, the fabric is at the required longitudinal tension. If feed rolls 24, 26 are driven by motor 28 at too slow a speed, the pull on the fabric, by feed rolls 106, 108 will pull tension roll 32 upwardly, in a counter clockwise direction, against the air pressure in cylinder 42. Such upward movement of tension roll 32 changes the setting of rheostat 30, and increases the speed of motor 28 and the feed speed of feed rolls 24, 26. As the feed speed of feed rolls 24, 26 increase, tension roll 32 will be moved downward, in a clockwise direction, by the air pressure in cylinder 42. As tension roll 32 moves downward, clockwise, rheostat 30 is reset, slowing down motor 28 and the feed speed of feed rolls 24, 26. Thus, tension roll 32 maintains the required tension on the fabric as it enters chamber A.

Tension roll 118 and rheostat 126, through the control of motor 166, regulates the longitudinal tension on the fabric between feed rolls 106, 108 and heated drums 176, 178, 180, 182, 184 in a similar manner. As tension roll 1 18 is moved upwardly, by the fabric, in a counter clockwise direction, rheostat 126 slows motor 126 down and, as tension roll 118 moves downwardly, in a clockwise direction, increases the speed of motor 166. Similarly, tension roll 202 controls motor 292 and the longitudinal tension on the fabric as the fabric is discharged from heated drums 176 to 184, by speeding up and slowing down the speed of the rewinding of the treated fabric.

In the apparatus of the instant invention and because of the vaporization of the ammonia, the temperature in the atmosphere of chamber A is at about 20 F. and, in chamber B, about 0 F., the temperature in chamber B being raised, to some extent, by the temperature of the heated drums. In chamber A, the temperature of the fabric is at about 30 F. The ammonia saturated fabric, as it passes around heated drums 176, 178, 180, 182, is heated and, as the fabric passes into heated chamber C, the temperature of the fabric is further raised by the heated atmosphere of chamber C. As the fabric passes the steam jets in chamber C, the steam from the 1 jets removes residual ammonia from the treated fabric.

Where the fabric is treated with resin, along with the treatment with ammonia, in trough 112, chamber C, in addition to the steam jets, or in lieu thereof, may be provided with jets of high temperature gas or flames, to cure or heat set the resin.

The treated fabric leaving chamber C is relatively dry. Where transverse tensioning of the fabric, as it passes through frame 340, is required, the moisture content of the treated fabric may be so low that transverse tensioning in frame 340, cannot be applied. Where this condition exists and transverse tensioning in frame 340 is required, the fabric may be sprayed with water at the water spray 339. The fabric, as it leaves the transverse tensioning frame 340, is dried by drier drum 344. The felt 348 on the drier maintains the transverse tensioned width of the fabric, as the fabric is dried.

The speed and, hence, the time that the fabric remains in the chambers and undergoing treatment, is regulated by feed rolls 106, 108, driven by motor 110. By setting motor 110 and feed rolls 106, 108 at a predetermined speed, the treatment time of the fabric is controlled. In addition as has been mentioned above, retention time of the fabric, undergoing treatment in the chambers can be increased, or decreased, by varying the loops of the fabric around the guide rolls in chambers A, B and C.

In longitudinal tensioning of the fabric, i.e., tensioning of the fabric in the feed direction as the fabric is fed into chamber A and feed rolls 106, 108 is controlled by regulating the speed of feed rolls 24, 26 relative to the speed of feed rolls 106, 108. Longitudinal tensioning of the fabric away from feed rolls 106, 108 is controlled by the feed speed of heater drums 176, 178, 180, 182, 184, driven by motor 166. Longitudinal tensioning of the fabric from the heater drums is controlled by motor 392 and drive rolls 350, 358. By regulating the air pressure in the control cylinders associated with the various tension rolls, the speed relationship between the various feed rolls with feed rolls 106, 108 can be varied and the longitudinal tension of the fabric, in the direction of fabric feed, regulated.

In addition to the fabric treatments hereinabove described, with some fabrics it may also be desired to compact or mechanically shrink the fabric, longitudinally of the fabric, after such fabric has undergone the aforedescribed treatment. This can be accomplished, after treatment, by unrolling the fabric from roll 402, passing the unrolled fabric through compressive shrinking apparatus, such as shown and described in U. S. Pat. No. 2,721,370, and rerolling the fabric. Such unrolling, compressive shrinking and rerolling of the fabric requires further fabric handling. Thus, in FIGS. 1C, 2C there is shown apparatus for compressive shrinking, longitudinally ol'the fabric, before such fabric is finally dried and rolled.

Referring to FIGS. 1C, 2C, compressive shrinker, generally designated 410, is positioned at the end of transverse tensioning frame 340, between the end of frame 340 and drier drum 344 in the path of travel of the fabric. Compressive shrinker 410 employs heated cylinder drum 412, which may be hollow and heated with steam, mounted for rotation in frame 414 and driven, by motor 292, through gear box 416, pulley 418, belt 420 and gears 422, 424. Intake roll 426 is rotatably mounted, at its opposite ends, in arms 428, 430. Each arm 428, 430 is pivoted by a pin 432 (FIG. 1C) on frame 414. Each arm 428, 430 is pivotally connected, at its upper end, by link 434 to nut 436 through which is threaded screw 438, rotatably mounted in frame 414. Endless rubber belt 440 extends partially around intake roll 426 and idler rolls 442, 444. Idler rolls 442, 444 are rotatably mounted on frame 414 with their axes parallel to the axis of rotation of drum 412. Idler roll 444 is mounted for adjustment on frame 414, by hand wheels 446, 448 to tighten or loosen belt 440 and adjust the pressure of belt 440 against drum 412.

The operating of the apparatus, modified as in FIGS. 1C, 2C, is the same as the operation of the apparatus in FIGS. 1A, 18, 2A, 2B with the exception, of course, that the treated fabric, as it is discharged from transverse tensioning frame 340 and before the fabric is fed to drier roll 344, is passed through compressive shrinker 410.

The operation of compressive shrinker 410 is more completely described in U. 5. Pat. No. 2,721,370. Intake roll 426 is adjusted to compress or squeeze rubber belt 440 against cylinder drum 412. The compression of belt 440 against drum 412 and the subsequent contraction and slowing down lengthwise of the belt surface and the fabric adhering to the surface of belt 440 longitudinally compresses, compacts and compressively shrinks the fabric lengthwise of the fabric and the path of feed of such fabric through compressive shrinker 410. The adjustment of intake roll 426 to compress belt 440 against drum 412 and the speed of drum 412, drier drum 344, 346 and the drier belt are regulated to afford the desired compressive shrinkage of the fabric.

The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible.

We claim 1. A machine for treating fabric comprising, a treatment chamber, first feed means for feeding fabric at a first speed into said chamber, first control means for varying said first speed, means in said chamber for impregnating said fabric in said chamber with liquid ammonia, a second feed means for removing ammonia treated fabric from said impregnating means and a second control means after said second feed means for varying said first speed of said first feed means relative to the speed of said second feed means for applying a predetermined longitudinal tension to said fabric between said first and second feed means.

2 A machine for treating fabric, as recited in claim 1, said machine including means for saturating the atmosphere in said chamber with ammonia vapor.

3 A machine for treating fabric, as recited in claim 1, including means for longitudinally compressing said fabric.

4. A machine for treating fabric, as recited in claim 3, in which said means for longitudinally compressing said fabric comprises a drum, and endless rubber belt for engaging said drum and means for compressing said endless rubber belt against said drum.

5. A machine for treating fabric, as recited in claim 4, in which said means for compressing said endless rubber belt against said drum comprises a roll and means for moving said roll toward and away from said drum to increase and decrease the compression of said belt against said drum.

6. A machine for treating fabric comprising a treatment chamber, first feed means for feeding fabric at a first speed into said chamber, means in said chamber for impregnating said fabric in said chamber with liquid ammonia, second feed means for removing ammonia treated fabric from said chamber, control means intermediate said first and second feed means for varying said first speed of said first feed means relative to the speed of said second feed means for applying a predetermined longitudinal tension to said fabric between said first and second feed means, a first vent means at the top of said treatment chamber, a second vent means near the bottom of said treatment chamber, valve means in said first vent means for opening and closing said first vent means and valve means in said second vent means for opening and closing said second vent means.

7. A machine for treating fabrics, as recited in claim 6, including means in said treatment chamber for impregnating the atmosphere in said treatment chamber with ammonia vapor.

8 A machine for treating fabric, as recited in claim 7, in which said means for impregnating the atmosphere in said treatment chamber includes a trough, means for feeding liquid ammonia to said trough and means for heating said liquid ammonia in said trough.

9. A machine for treating fabric comprising, a treatment chamber, first feed means for feeding fabric at a first speed into said chamber, second feed means in said chamber for feeding said fabric at a second speed, means in said chamber for impregnating said fabric in said chamber with liquid ammonia, third feed means for removing ammonia treated fabric from said chamber, control means intermediate said first and second feed means for varying said first speed of said first feed means relative to said second speed of said second feed means for applying a predetermined longitudinal tension to said fabric between said first and second feed means and control means intermediate said second and third feed means for varying the feed speed of said third feed means relative to said second feed means for applying a predetermined longitudinal tension to said fabric between said second and third feed means.

10. A machine for treating fabric, as recited in claim 9, said machine including means for saturating the atmosphere in said treatment chamber with ammonia vapor.

11. A machine for treating fabric, as recited in claim 10, in which said treatment chamber includes a first and second chamber and means in said second chamber for heating said ammonia impregnated fabric.

12. A machine for treating fabric, as recited in claim 11, in which said second chamber includes a fourth feed means for feeding said fabric intermediate said second and said third feed means, control means intermediate said second and said fourth means for varying the feed speed of said fourth feed means relative to said second feed means for applying a longitudinal tension to said fabric between said second and said fourth feed means and control means intermediate said fourth and said third feed means for varying the feed speed of said third feed means relative to said fourth feed means for applying a longitudinal tension to said fabric between said fourth and said third feed means.

13. A machine for treating fabric, as recited in claim 12, in which said machine includes tensioning means intermediate said impregnating means in said first chamber and said heating means in said second chamber for applying transverse tension to said fabric as said fabric is fed longitudinally through said transverse tensioning means.

14. A machine for treating fabric, as recited in claim 13, in which said machine includes a third chamber and means in said third chamber for steaming said fabric.

15. A machine for treating fabric, as recited in claim 14, in which said first and second chambers include means for venting air from said chambers as the atmosphere in said chambers is being saturated with ammonia vapor and means for venting said ammonia vapor from said chambers when said machine is being shut down.

16. A machine for treating fabric, as recited in claim 15. in which said third chamber includes means for venting steam from such third chamber.

17. A machine for treating fabric, as recited in claim 16. in which said means in said treatment chamber for impregnating said fabric with liquid ammonia includes means for simultaneously treating said fabric with resin and said third chamber includes means for curing said resin.

18 A machine for treating fabric, as recited in claim 17, in which said means for curing said resin includes hot gas jets.

19. A machine for treating fabric, as recited in claim 18, in which said means for curing said resin includes flame jets in said third chamber.

UNITED STATES PATENT oFFICE CERTIFICATE OF (IQRRECTION Patent No. .3,664,l58 Dated May 23, 1972 Inventor(s) OLAV SKAA'I'HUN ET AL.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the Title page, first column, in the heading, after the Application Number, insert the following priority information:

Norway No. 3565/69 Priority claimed: v

filed September 5, 19690 Signed and sealed this 16th day of April 197M,

(SEAL) Attest: EDWARD MFLETCHER,JR. Co MARSHALL DANN Attestlng Officer Commissioner of Patents F P0405) (w'ss) USCOMM-DC 60376-P69 a US GOVERNMENT PRINTING OFFICE Z 939 0-355-334, 

4. A machine for treating fabric, as recited in claim 3, in which said means for longitudinally compressing said fabric comprises a drum, and endless rubber belt for engaging said drum and means for compressing said endless rubber belt against said drum.
 5. A machine for treating fabric, as recited in claim 4, in which said means for compressing said endless rubber belt against said drum comprises a roll and means for moving said roll toward and away from said drum to increase and decrease the compression of said belt against said drum.
 6. A machine for treating fabric comprising a treatment chamber, first feed means for feeding fabric at a first speed into said chamber, means in said chamber for impregnating said fabric in said chamber with liquid ammonia, second feed means for removing ammonia treated fabric from said chamber, control means intermediate said first and second feed means for varying said first speed of said first feed means relative to the speed of said second feed means for applying a predetermined longitudinal tension to said fabric between said first and second feed means, a first vent means at the top of said treatment chamber, a second vent means near the bottom of said treatment chamber, valve means in said first vent means for opening and closing said first vent means and valve means in said second vent means for opening and closing said second vent means.
 7. A machine for treating fabrics, as recited in claim 6, including means in said treatment chamber for impregnating the atmosphere in said treatment chamber with ammonia vapor. 8 A machine for treating fabric, as recited in claim 7, in which said means for impregnating the atmosphere in said treatment chamber includes a trough, means for feeding liquid ammonia to said trough and means for heating said liquid ammonia in said trough.
 9. A machine for treating fabric comprising, a treatment chamber, first feed means for feeding fabric at a first speed into said chamber, second feed means in said chamber for feeding said fabric at a second speed, means in said chamber for impregnating said fabric in said chamber with liquid ammonia, third feed means for removing ammonia treated fabric from said chamber, control means intermediate said first and second feed means for varying said first speed of said first feed means relative to said second speed of said second feed means for applying a predetermined longitudinal tension to said fabric between said first and second feed means and control means intermediate said second and third feed means for varying the feed speed of said third feed means relative to said second feed means for applying a predetermined longitudinal tension to said fabric between said second and third feed means.
 10. A machine for treating fabric, as recited in claim 9, said machine including means for saturating the atmosphere in said treatment chamber with ammonia vapor.
 11. A machine for treating fabric, as recited in claim 10, in which said treatment chamber includes a first and second chamber and means in said second chamber for heating said ammonia impregnated fabric.
 12. A machine for treating fabric, as recited in claim 11, in which said second chamber includes a fourth feed means for feeding said fabric intermediate said second and said third feed means, control means intermediate said second and said fourth means for varying the feed speed of said fourth feed means relative to said second feed means for applying a longitudinal tension to said fabric between said second and said fourth feed means and control means intermediate said fourth and said third feed means for varying the feed speed of said third feed means relative to said fourth feed means for applying a longitudinal tension to said fabric between said fourth and said third feed means.
 13. A machine for treating fabric, as recited in claim 12, in which said machine includes tensioning means intermediate said impregnating means in said first chamber and said heating means in said second chamber for applying transverse tension to said fabric as said fabric is fed longitudinally through said transverse tensioning means.
 14. A machine for treating fabric, as recited in claim 13, in which said machine includes a third chamber and means in said third chamber for steaming said fabric.
 15. A machine for treating fabric, as recited in claim 14, in which said first and second chambers include means for venting air from said chambers as the atmosphere in said chambers is being saturated with ammonia vapor and means for venting said ammonia vapor from said chambers when said machine is being shut down.
 16. A machine for treating fabric, as recited in claim 15, in which said third chamber includes means for venting steam from such third chamber.
 17. A machine for treating fabric, as recited in claim 16, in which said means in said treatment chamber for impregnating said fabric with liquid ammonia includes means for simultaneously treating said fabric with resin and said third chamber includes means for curing said resin.
 18. A machine for treating fabric, as recited in claim 17, in which said means for curing said resin includes hot gas jets.
 19. A machine for treating fabric, as recited in claim 18, in which said means for curing said resin includes flame jets in said third chamber. 